SBSettings (gives you access to controls with the swipe of a finger), BlackKeyboard (love this one), 5 Icon Dock, Winterboard (themes/customizing look of springboard), CustomNCBackground (lets you change the image on your notification center dropdown bar), also WeKillBackground for NC is a sweet tweak that gives you a button on your notification center dropdown screen, that kills all running apps. Also PandoraSkips is a cool tweak allows you to skip through songs without limits.

There are lots more. I actually just jailbroke a few days ago, so I'm still learning and finding out others..

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